A quartet of exoplanets has been discovered orbiting a pair of young stars

A team of international astronomers has used NASA's TESS spacecraft to identify four exoplanets that are orbiting a pair of related young stars. The stars are called TOI 2076 and TOI 1807. Astronomers believe the exoplanets could provide details on a little-understood stage of planetary evolution. Planets in both systems are in a transitional or teenage phase of their lifecycle.The planets are described as not being newborn but also not settled down. Astronomers hope learning more about planets in the teen stage could help them understand older planets in other systems. TOI 2076 and TOI 1807 reside about 130 light-years away from Earth and have approximately 30 light-years between them. The stars are located in the northern constellations of Bo├Âtes and Canes Venatici, respectively.

Both of the stars are too far apart to orbit each other, but they do have shared motion suggesting their related or born from the same cloud of gas. Both the stars experience stellar flares that are much more energetic and occur more frequently than those produced by the sun. The stars also produce about ten times more UV light than they will when they reach the sun's age.

Astronomers believe the sun could have been equally as active at one time in its past and that these systems could provide a window into the early conditions of our solar system. TOI 2076 was initially discovered by Alex Hughes while working on an undergraduate project at Loughborough University in England. The team discovered three mini-Neptunes, which are worlds between the diameter of Earth and Neptune orbiting the star. The innermost planet is called TOI 2076 b and is about three times the size of Earth, orbiting the star every ten days. TOI 2076 c and d are both a bit more than four times the size of Earth orbiting the star every 17 days.

TOI 1807 has only one known planet called TOI 1807 b orbiting its star every 13 hours. Astronomers say that exoplanets with such short orbits are very rare, with TOI 1807 b being the youngest example discovered yet.